Purpose: Fluorine-18 fluorodeoxyglucose (F-18 FDG) positron emission tomographic (PET) imaging can be a vital tool in the evaluation and preoperative staging of pulmonary neoplasms. Imaging studies on the gamma camera using coincidence PET (co-PET) were introduced recently into clinical practice. This prospective study assessed the efficacy of co-PET for identifying primary tumors, mediastinal lymph node involvement, the presence of distant spread, the effect on disease staging, and influence on disease management.
Patients and methods: Sixty consecutive patients with 61 lung tumors were enrolled in the study (36 men, 24 women; age range, 32-87 years; mean age, 67 years). Histopathologic confirmation was obtained in 58 patients (59 tumors).
Results: In assessments of a primary lesion to establish its malignant or benign nature, the sensitivity rate of co-PET was 96% (53 of 55 lesions), the specificity rate was 83% (5 of 6 lesions), and the accuracy rate was 95% (58 of 61 lesions). In the co-PET assessment of lymph node involvement in which histopathologic confirmation was obtained (n = 32), the sensitivity rate was 89% (8 of 9 lesions), the specificity rate was 91% (21 of 23 lesions), and the accuracy rate was 91% (29 of 32 lesions). Previously unknown distant metastases were correctly identified in eight patients, but five false-positive lesions were detected in the brain. Disease staging was correctly altered in 20 patients (33%), and disease management plans were changed in 20 patients (33%) based on the co-PET findings. Unnecessary surgery was obviated in six patients (10%). One patient was given the chance for curative treatment based on the findings of the co-PET study.
Conclusion: The evaluation of patients with lung neoplasms using F-18 FDG coincidence detection appears to be reliable.